This Old Tornado

Introduction: This Old Tornado

Description of how to build a tornado model. This instructable is faster paced as an old model tornado prototype is restored and operated. This design is by no means bomb proof and should only be operated under close supervision.

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Step 1: Parts of the Tornado Model

In this step, plans for the foam insulation and chamber windows are given.

Step 2: Assemble Tornado Chamber Base

In this step, the base box of the tornado chamber is assembled with duct tape and the foam insulation Panels described in step 1:

Step 3: Attach Light to Chamber Top Panel

The Halogen Light Fixture is attached to the top panel of the tornado chamber with duct tape:

Note the bulb face is flush with the top of the chamber panel. The hole for the clamp of the light fixture is also made flush with the top of the chamber panel by adding another piece of duct tape to the base of the hole.

Step 4: Position and Test Humidifier

The humidifier is positioned, filled with water and tested. Note the output of the fan into the nebulizing chamber has its opening restricted so the fog exits the nozzle with a slow laminar flow:

Step 5: Assemble Tornado Chamber

This step describes the assembly of the chamber.

Step 6: Operation of This Old Tornado

The tornado power is turned on. The flow of the fog has been slowed and gently fills the chamber floor. In the video below, the power is cut to the fan but left on for the light and fog.

Other tricks and effects:

Interacting with the tornado by inserting your hand in one of the air intakes (watch out not to topple the chamber as in this design there is nothing holding the top on):

Interacting by blowing gently in an air intake:
Disturbing the vortex in this way makes the air flow more like what happens with a real tornado. The air is rarely totally still and many of the interesting twists are caused by slight disturbances in the air entering the vortex.

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    4 Discussions


    4 years ago

    Thank you for the post! It looks like you rely on the lamp to generate heat and the motion of the fog entering the chamber at an angle to generate the tornado, is that correct? What does the fan do, then, if the lamp is the primary tornado generator? Does the fan assist the turbulence further?


    Reply 4 years ago

    The fan moves the air, drawing it into the chamber to form a rotating cylinder of air and exhausting the air along the axis of rotation to create the vortex. The lamp illuminates the fog to visualize the vortex. So convection plays an insignificant role in the air motion (even though real tornadoes are powered by differences in air temperature) for this display. Does that clarify how it works?


    10 years ago on Introduction

    great instructable and very similar to my tornado machine. if you used better materials like wood and painted it you could have a good lookin tornado machine.


    Reply 10 years ago on Introduction

    I'm sure your design would hold up much better than this prototype. The science museum where I used this design eventually bought a permanent commercial tornado exhibit.